Starlight: List of Problems

Over 20,000 problems available. AMC 8/10/12 and AIME problems from 2010-2023; USAJMO/USAMO problems from 2002-2023 available. USACO problems from 2014 to 2023 (all divisions). Codeforces, AtCoder, DMOJ problems are added daily around 04:00 AM UTC, which may cause disruptions.

Need help searching? Click for format/examples of problems

AMC 8: [year] AMC 8 Problem #, Ex: 2013 AMC 8 Problem 1
AMC 10: [year] AMC 10A Problem # OR [year] AMC 10B Problem #, Ex: 2015 AMC 10A Problem 16
AMC 12: [year] AMC 12A Problem # OR [year] AMC 12B Problem #, Ex: 2021 AMC 12B Problem 25
AIME: [year] AIME I Problem # OR [year] AIME II Problem #, Ex: 2013 AIME I Problem 8
USAJMO/USAMO: [year] USAJMO/USAMO Problem #, Ex: 2023 USAJMO Problem 1
Codeforces: Codeforces [contest id (e.g. 101)][problem id (e.g. A, B, C)]: [Codeforces problem name], Ex: Codeforces 1336F: Journey
AtCoder: AtCoder [contest id (e.g. ABC314, ARC164, ZONE2021)]: [problem id (A, B, C)]. [Problem name], Ex: AtCoder ZONE2021: E. Sneaking
DMOJ: DMOJ [contest name (if applicable)] [problem number (e.g. P1)] - [Problem name], Ex: DMOJ Yet Another Contest 3 P1 - Shell Swap Scam
USACO: [year] [contest month (e.g. January, US Open)], [division (e.g. Gold)]: [Problem name], Ex: USACO 2023 US Open Contest, Bronze: Rotate and Shift

ID	Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)
12151	AtCoder CF16-FINAL: B. Exactly N points
12150	AtCoder CF16-FINAL: A. Where's Snuke?
12149	AtCoder CF16-EXHIBITION: B. Exact Payment
12148	AtCoder CF16-EXHIBITION: A. Distance Pairs
12147	AtCoder CODE-FESTIVAL-2015-QUALB: D. Squares, Pieces and Coloring
12146	AtCoder CODE-FESTIVAL-2015-QUALB: C. Hotel
12145	AtCoder CODE-FESTIVAL-2015-QUALB: B. Grading
12144	AtCoder CODE-FESTIVAL-2015-QUALB: A. Double String
12143	AtCoder CODE-FESTIVAL-2015-QUALA: D. 壊れた電車
12142	AtCoder CODE-FESTIVAL-2015-QUALA: C. 8月31日
12141	AtCoder CODE-FESTIVAL-2015-QUALA: B. とても長い数列
12140	AtCoder CODE-FESTIVAL-2015-QUALA: A. CODE FESTIVAL 2015
12139	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: J. N個のバケツ
12138	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: I. 風船ツリー
12137	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: H. 焼肉の達人
12136	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: G. スタンプラリー
12135	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: F. 歩くピアニスト
12134	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: E. ショートコーディング
12133	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: D. 足ゲームII
12132	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: C. 寿司タワー
12131	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: B. ダイスゲーム
12130	AtCoder CODE-FESTIVAL-2015-FINAL-OPEN: A. コード川柳
12129	AtCoder CODE-FESTIVAL-2015-EXHIBITION: B. TRAX
12128	AtCoder CODE-FESTIVAL-2015-EXHIBITION: A. 高橋王国と青木王国
12127	AtCoder CODE-THANKS-FESTIVAL-2018: H. Median Game
12126	AtCoder CODE-THANKS-FESTIVAL-2018: G. Sum of Cards
12125	AtCoder CODE-THANKS-FESTIVAL-2018: F. Coins on the tree
12124	AtCoder CODE-THANKS-FESTIVAL-2018: E. Union
12123	AtCoder CODE-THANKS-FESTIVAL-2018: D. Concatenation
12122	AtCoder CODE-THANKS-FESTIVAL-2018: C. Pair Distance
12121	AtCoder CODE-THANKS-FESTIVAL-2018: B. Colored Balls
12120	AtCoder CODE-THANKS-FESTIVAL-2018: A. Two Problems
12119	AtCoder CODE-THANKS-FESTIVAL-2017: H. Union Sets
12118	AtCoder CODE-THANKS-FESTIVAL-2017: G. Mixture Drug
12117	AtCoder CODE-THANKS-FESTIVAL-2017: F. Limited Xor Subset
12116	AtCoder CODE-THANKS-FESTIVAL-2017: E. Coin Authentication
12115	AtCoder CODE-THANKS-FESTIVAL-2017: D. Bus Tour
12114	AtCoder CODE-THANKS-FESTIVAL-2017: C. Factory
12113	AtCoder CODE-THANKS-FESTIVAL-2017: B. Concatenated Palindrome
12112	AtCoder CODE-THANKS-FESTIVAL-2017: A. Time Penalty
12111	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: H. 穴あきケーキ
12110	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: G. カメレオン
12109	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: F. お祭りとお菓子
12108	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: E. ノイズ除去
12107	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: D. 暴露
12106	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: C. 集合写真
12105	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: B. 袋とボール
12104	AtCoder CODE-THANKS-FESTIVAL-2015-OPEN: A. 金庫
12103	AtCoder CODE-THANKS-FESTIVAL-2014-B-OPEN: H. しりとりゲーム
12102	AtCoder CODE-THANKS-FESTIVAL-2014-B-OPEN: G. 石取りゲーム

Problem Name (click to add insights/hints, view summary of insights/hints and similar problems)

12151

AtCoder CF16-FINAL: B. Exactly N points

12150

AtCoder CF16-FINAL: A. Where's Snuke?

12149

AtCoder CF16-EXHIBITION: B. Exact Payment

12148

AtCoder CF16-EXHIBITION: A. Distance Pairs

12147

AtCoder CODE-FESTIVAL-2015-QUALB: D. Squares, Pieces and Coloring

12146